The present invention relates to a rotor, and to an electric machine having such a rotor, and to a manufacturing method for the rotor.
The following discussion of related art is provided to assist the reader in understanding the advantages of the invention, and is not to be construed as an admission that this related art is prior art to this invention.
A rotor of a type involved here has a plurality of permanent magnets which are arranged around a shaft of the rotor in the circumferential direction in order to provide permanent excitation. A flux conducting device is provided in the rotor for conducting a magnetic flux of the permanent magnets.
Rotors can be provided to form a soft-magnetic base body composed of laminated metal sheets as the flux conducting device. The laminated metal sheets are stacked up in layers to form a laminated core, with an electrically insulating layer being provided between the individual sheets in order to avoid eddy currents. A hole is punched out in the center of the individual sheets so that following its completion the laminated core will have a passage aperture through which the shaft of the rotor is inserted. The laminated core can thus be joined to the shaft by means of an interference fit. Furthermore, cutouts are also punched out on the outer edge of the laminated sheets such that pockets are produced in the finished laminated core in the circumferential direction, into which pockets permanent magnets for producing a permanent excitation of the rotor can be embedded. The term “circumferential direction” has hereby its usual meaning, i.e. in relation to an axis of rotation of the rotor, the directional vectors of the circumferential direction lie in a plane perpendicular to the axis of rotation of the rotor and are tangentially aligned on a circle around the axis of rotation in the plane.
It would be desirable and advantageous to provide an improved rotor with permanent excitation, improved electric machine having such a rotor, and improved method for manufacturing a rotor to obviate prior art shortcomings.